House electric



C. B. MILLS INCLOSED VENTILATED MOTOR Filed Nov. 21, 1918 2 Sheets-Sheet 2 INVENTOR (ha/er 5. 0717/5 WITNESSES:

ATTORNEY Patented Dec. 2, 1924.

UNITED STATES PATENT OFFICE.

CHESTER B. MILLS, OF EAST MCKEESFORT. PENNSYLVANIA, ASSIGNOR- TO WESTING- HOUSE ELECTRIC' & DIANUFACTURING COMPANY, A CORPORATION OF PENNSYL- VANIA.

INCLOSED VENTILATED MOTOR.

Application filed November 21, 1918. Serial No. 268,571.

Tod] whom-7t may concern 1 Be it known that Ltlnasrnn B. Mints. a citizen of the United States, and a resident of East McKeesport, in the county of Al- 6 legheny and State of Pennsylvania, have 'inve nteda' ne w' and useful Improvement in Inelos'ed Ventilated hiotor's, of which the following is a specification. 4

lily-invention relatesto dynamo-electric machines'fhaving' particular relation, to ma chines o fjthe inc losed type wherein a cur rent of air 'is'i'co'n'tinuously circulated within the frame thereof without,.at any time, comingj into direct engagement with the outside air, and it .-h a s{ for,1itsobject to provide a novel'g system of ventilation for use in machines of the above indicatedcharacter' whichrnay be simple andinexpensiverawings, ,Fig; 1 is I 11} e til elktl 9w embodying y invention; andi Fig. 2 is an. end elevational viewiof the lllOtOlflShQWll in Fi 1; Fig. 3is asectional view, similar to ig. 1, of 1;slight'modification thereof; and Fig. 4 1.5m end elevationio f the structure shown in FigLB. v

I-Ie'retofor'e, in niills ,wherein the atmosphere contains lint such. for example, as cotton mills,-motors of.the open ventilated type have been used, the ventilating spaces hein; relatively large so that they would I not be clogged with particles of lint ad lutl'lliif to the sides thereof. However. the lint forms coatings upon the windings and in the ventilating spaces which prevent the,

proper radiation of heat. thus causing the machine to overheat seriously and rendering it necessary to disassemble and clean the. machine at least twice a year.

By my invention. I provide a dynamo- (-lCCtl'lC machine provided with an internal inclosed and an external air circuit which are brought into close proximity to each other in a novel manner and in which the external circuit is adapted to be readily cleaned.

For a better understanding of my invcntion, reference may now be had to the drawings in which I show a motor provided with a stator 1 comprising laminations 2, end frames 3 and 4, and a rotor 5 comprising a shaft 6 and rotor laminations 7. The motor is inclosed by end bells 8 and 9 which prevent the entrance of outside air thereinto. The externalair passages inelude a fan chamber 13. within which a fan staggered groups, thus providing projections 15 that extend into the external-air passage 11 and serve to churn the air pasing therethrough. The internal or inclosecair path include-s longitudinal ducts 16 through the.rotor la1ninat ions 7, the spaces between, the armature and the enclosing end members8 and 9 and a substantially circumferential chamber 17 formed by a casing 18 that encloses, but is spaced from,

the casing member 12. Theair in this passage isnioved by means of a fan 19. Al

though the air passage17 is substantially circumferential, the air is moved therethrough in a longitudinal direction. Thus.

it will be seen that the air passing through the passage 11 will, on one side, engage and e churned by the outer peripheries of the laminations 2 and, on the other side, will engage the casing member 12 to \vhirh is transmitted a portion of the heat energy of the air passing through the passage 17. The passage 17 is provided with a reiativel -x large external surface, thus ailmving -l large amount of space for heat radiation on both sides of the passage.

In the modification disclosed in Figs. 3 and 4, the external-air passage includes an entrance duct 10, a circumferential passage 11 and an exit duct 24, all similar to the structure described in connection with Figs. 1 and 2. The internal passage 17, however, is somewhat different, since it includes longitudinal air ducts 16, the spaces between the end-enclosing members 8 and 9 and the laminations, and at tortuous longitudinal passage 20 formed by openings 21 punched through a series of alined projections 22 on the peripheries of the stator laminations 2. The air in this path is prevented from coming into engagement with the air in the external path by means of arcuate plates 23 which extend between the projections 2'3 and are attached to rojections on the sides thereof, thus forming a good radiating surface adjacent the external air passage The chief distinction between the structure shown in Fi 1 and the structure shown in'Fig. 3 is trat, in Fig. 1, the internal-air passa e includes the external chamber on the periphery of the machine, while, in the mod ification shown in Fig. 3, the external-air passage includes the external air chamber. A fan-member 14, in a separate chamber 13. draws air from the outside and forces it into the passage 11 through the port 10 sub stantially as in the structure shown in Fig.' 1.

.From the foregoing description it will be understood by those skilled in the art that a motor constructed in accordance with my inventionwill be almost entirely free from foreign matter derived from the atmosphere in which it is operating, and the portions that are not free from such matter may be readily removed for cleaning.

Throughout this specification and the claims attached hereto, the terms internal circuit or path are to be understood as delining apassage the traversing medium of wlnch is not continuously renewed from the outside atmosphere but is continuously circulated within the enclosing casing. The terms external air path are to be understoodas defining a passage through which air from outsideof the machine is continuously circulated.

Although I have shown my invention in only two forms, it will he Ob\ 'iOUS to those skilled in the art that it is not so limited but is susceptible of various minor changes and modifications without departing from the spirit thereof, and I desire, therefore. that only such limitations sha l be placed thereupon as are imposed by the prior art. or are specifically set forth in the appended claims.

an inclosed dynaruo-electric ma chine. a stator member of laminated struc ture, two casings disposed adjacent to said strlwutre 331d forming inner and outer circuluterential chambers, the outer peripherv of said laminated structure constituting one of th walls of said inner chamber, said inner chamber being in connnuuication with the exterior atmosphere and the outer chamber being closed with respect thereto, and means for circulating independent currents of air through said chambers.

in an incic-sed dynamo-electric rna chine, stator member of laminated structure. two circumferential casings of ditlerent diameters circumferentially enclosing said structure and spaced therefrom and from each other to form inner and outer circumferential chambers, the outer periphery of said laminated structure constituting the inner wall of said iurrer chamber, said inner chamber being in communication with the exterior atmosphere and the outer charnher being closed with respect thereto, and means for circulating independent currents of air through said chambers.

3. In an inclosed dynamo-electric machine, a stator member of laminated structure, two circumferential casings of different radii of curvature circumferentially enclosing said structure and spaced therefrom and from each other to form inner and outer circumferential chambers, the outer periplror of said laminated structure being of irregular contour and constituting the inner wall of said inner chamber, and means for causing a circumferential current of air in said inner chamber and for causing an independent longitudinal current of arr in said outer chamber.

In testimony whereof, I have hereunto z'hss-rihed my name this 31st day of Oct,

CHESTER B. MILLS. 

